This is a proposal to initiate a psychiatric epidemiology research unit. The purpose of this unit is to promote understanding of the distribution of psychological illness, psychosomatic illness and social impairment with respect to time, geography, and a variety of dimensions of social space. The understanding to be provided by these studies will give leads to etiology and will provide an improved basis for planning a mental health program for the State of Rhode Island. The full gamut of techniques for assessing mental health and related phenomena at the community level will be used by this unit in due course of time. Initially, the emphasis will be on the epidemiologic analysis of mental hospital data, on the development of plans for an interview survey of depression, and on the establishment of a follow-up system which will allow the evaluation of environmental effects on the mental health of discharged mental patients. Later steps will include studies of psychosomatic and related conditions of social impairment, i.e., of faulty social interactions, and analysis of data from psychiatric clinics. It is possible to do all this in Rhode Island because this is a small centripetally oriented state with a mental health service that uses computers extensively for the storage of its data. The thing that is new about this study is the use of a wide variety of techniques on one population in order to get multiple bearings on the same points.